1. The Field of the Invention
The present invention generally relates to preventing contamination of fiber optical components. More particularly, the invention relates to dust cap covers for fiber optic components.
2. Related Technology
Because of their high bandwidth and reliable high-speed data transmissions, fiber optic networks are increasingly becoming a popular mode of communication. These high-speed communication networks utilize optical-electronic components such as optical transceivers in transmitting information via the network from a transmission node to a reception node. An optical transceiver at the transmission node receives an electrical signal from a network device, such as a computer, and converts the electrical signal via a laser to an optical signal. The optical signal can then be emitted by a transceiver and transmitted in a fiber optical cable via the optical network, such as a local area network (LAN) backbone, for instance.
The optical signal is then received by a reception node of the network. Once received by the reception node, the optical signal is fed to another optical transceiver for conversion via a photo-detector into electrical signals. The electrical signals are then forwarded to a host, such as a computer, for processing. The optical transceivers described above have both signal transmission and reception capabilities; thus, the transmitter portion of the transceiver converts an incoming electrical signal into an optical signal, whereas the receiver portion of the transceiver converts an incoming optical signal into an electrical signal.
Connections between an optical transceiver and corresponding optical network can include a number of intermediate components, such as, for example, patch cables and optical hubs. Thus, efficient communication over an optical network depends, at least in part, on the quality and reliability of these intermediate components. Accordingly, damage to or contamination of any of these intermediate components can reduce throughput or otherwise adversely affect communications. For example, contaminated components in an optical communication path can degrade return loss, reduce link budget, increase bit errors, and cause other problems in an optical link. If damage or contamination is significant, communication over an optical network may not be possible.
Accordingly, preventing the contamination of optical components is of increased importance to entities that utilize optical networks for data communication. In response to the increased importance, specifications directed to the cleanliness of optical components are currently being developed by industry standards bodies. Subsequent to development of these industry standards and as a result of the general demand for more efficient and reliable optical components, many entities will demand optical components that meet these new industry standards.
To reduce potential contamination, many vendors use existing dust caps or end covers (hereinafter refereed to collectively as “dust caps”) to protect the end face of optical components. Existing dust caps can prevent external dust and other debris from collecting on and thereby contaminating an optical component end face. Thus, existing dust caps may promote more efficient and reliable communication over optical networks. However, while providing protection from external contamination, the design of many existing dust caps can cause the dust caps themselves to contaminate optical component end faces
Several design features of existing dust caps can potentially cause this undesirable contamination. A first problematic design feature of existing dust caps are that the inner surface of existing dust caps contact, or bottom out, against the end face when inserted. Another problematic design feature of existing dust caps are that the opening in existing dust caps is too small, and an edge of the dust caps' opening may contact an optical component end face during it's insertion. Thus, as a result of many existing dust cap designs, any prior contamination of the dust cap (e.g., dust or debris) can be transferred to an optical component end face when the dust cap positioned to protect an optical component interface.
Another problem with some existing dust cap designs is caused when the dust cap is held against the shaft of the ferrule of an optical component. This design feature causes the dust cap to rub and slide against the ferrule shaft, which potentially transfers contaminants from the ferrule shaft to a corresponding optical component end face. Resulting contamination of an optical component may later make it difficult to connect one optical component to another (e.g., connecting an optical patch cable to an optical transceiver). This problem is often termed a “hard-plug” problem.
Contamination of fiber optic components caused by these undesirable features of the existing dust cap designs increase costs involved with cleaning, scrapping, trouble shooting, and handling customer returns of contaminated optical components. Accordingly, what would be advantageous are improved dust caps that are design to reduce contamination at optical component end faces.